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Full waveform (FW) LiDAR systems have gained momentum to map forest biophysical variables in the last two decades, owing to their ability to accurately estimate canopy heights and aboveground biomass. Currently, the Global Ecosystem Dynamics Investigation (GEDI) system on board of the International Space Station (ISS) is the most recent FW spaceborne LiDAR instrument for the continuous observation of earth's forests. Here, we assess the accuracy of GEDI FW data for the estimation of stand-scale dominant heights ( $H_{dom}$ ), and stand volume (V) using linear and nonlinear regression models based on several GEDI metrics. The models were calibrated and validated using in-situ data from Eucalyptus plantations in Brazil. Overall, the most accurate estimates of $H_{dom}$ and V were obtained using the stepwise regression, with an RMSE of 1.44 m (R2 of 0.92) and 24.39 m3.ha−1 (R2 of 0.90) respectively. The principal metric explaining more than 87% and 84% of the variability (R2) of $H_{dom}$ and V was the metric representing the height above the ground at which 90% of the waveform energy occurs.

Made available in DSpace on 2020-12-10T19:36:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-09-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel Growth and yield (G &Y) model systems aim at forecasting forest productivity. The lack of environmental variables to account for how water availability constrains eucalyptus production in Brazil, however, is argued to be a major drawback of these model systems. Thus, this study aimed to develop a stand-level G & Y model system that accounts for water availability (G & Y with SWD), highlighting its usefulness when applied for clonal eucalypt stands under drier climatic conditions. The dataset is composed of remeasurement information of sixteen research sites that span all climatic regions in Brazil. A total of eleven eucalypt clones were planted in single block plots at each site, and extra replications under the rainfall exclusion system were also installed for these eleven clones in fourteen sites. Linear algebra techniques were used to simultaneously fit a compatible set of prediction and projection basal area equations. A stand-level volume equation was also developed. These equations were validated through the use of an independent dataset composed of the rainfall exclusion plots. Finally, the accuracy and usefulness of a conventional G & Y model system applied to clonal eucalypt stands in Brazil was compared to the new proposed G & Y model system, which accounts for the impact of water availability in eucalyptus productivity. The prediction and projection basal area equations accounting for water availability displayed estimates in the order of 5% more accurate compared to the conventional basal area modeling. Stand-level volume estimates were 40% and 74% less biased through the use of the new G & Y model system. This result highlighted how useful and powerful the newly developed approach is, since the model system was capable to provide accurate estimates through the use of the rainfall exclusion plots. The new G & Y model system is a powerful alternative to estimate forest afforestation yield and is fully capable to accurately update forest inventories. The model system can also be used for projecting how forest growth may be impacted by short-term climate variation. North Carolina State Univ, Dept Forestry & Environm Resources, 2820 Faucette Dr,Campus Box 8001, Raleigh, NC 27695 USA Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, 310 W Campus Dr,Campus Box 169, Blacksburg, VA 24061 USA Forestry Sci & Res Inst, Via Comendador Pedro Morganti 3500, BR-13415000 Piracicaba, SP, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ 3780, BR-18610034 Botucatu, SP, Brazil Univ Sao Paulo, Dept Forest Sci, Ave Padua Dias 11, BR-13418900 Piracicaba, SP, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ 3780, BR-18610034 Botucatu, SP, Brazil CNPq: 249979/2013-6

Made available in DSpace on 2019-10-04T12:13:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-05-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anglo American Arauco Arborgen Arcelor-Mittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Lack of generalized equations has prevailed in Brazil, because it is assumed that localized or climate-specific equations are needed. This study aimed to develop generalized stem taper and volume equations applicable to 11 eucalyptus clones and evaluate if climate variation impacts the accuracy of the estimates. A total of 693 trees evenly distributed across 11 clones at 21 sites were used for model fittings and predictive validation. The penalized mixed spline (PMS) approach was developed for predicting stem taper and volume along the stem profile. The Schumacher and Hall (1933) equation was used to predict total tree volume, while volume ratio equations were applied to predict merchantable volume. For every fitted equation, an annual climatic variable was included to assess the improvement in model performance. The overall results highlighted that climatic variation does not need to be accounted for in stem taper and volume modeling. All of the equations displayed desirable accuracy, but the generalized PMS equation may be preferred when the forestry enterprise looks to furnish a range of multiple forest products. The generalized total tree volume equation, combined with the ratio equations, is highly recommended when the forestry enterprise produces a single product. North Carolina State Univ, Dept Forestry & Environm Resources, Raleigh, NC 27695 USA Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, Blacksburg, VA 24061 USA Forestry Sci & Res Inst, BR-13415000 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, BR-18610034 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, BR-18610034 Sao Paulo, Brazil CNPq: 249979/2013-6

Made available in DSpace on 2019-10-04T12:34:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Linking individual-tree and stand-level growth models is required for estimating future forest stand structure, while maintaining the desired accuracy for forest management decision making. There is a scarcity of studies addressing this issue for clonal Eucalypt stands in Brazil. Thus, this paper aims to develop a compatible individual-tree and stand-level growth and yield system for clonal Eucalypt stands in Brazil. The dataset used in this study is derived from remeasurement information of sixteen TECHS sites. At every site, eleven Eucalypt clones were planted in single block plots, while extra plots under a rainfall exclusion regime were also installed in fourteen sites. Prediction and projection diameter percentile equations were developed, as well as an individual-tree mortality equation and a generalized height-diameter equation. In addition, a detailed explanation of the structural architecture of the developed compatible growth and yield system is provided. Differences when forecasting forest afforestation and updating forest inventories were highlighted in order to provide the proper use of the developed growth and yield system. Finally, the individual-tree equations were validated through the use of the rainfall exclusion regime plots as was the growth and yield system when applied for prediction and projection purposes. The individual-tree level equations provided accurate estimates. The newly developed compatible growth and yield system also displayed unbiased and accurate estimates. The system achieved full compatibility between individual-tree and stand-level estimates and produced accurate stand table estimates. The growth and yield system presented is a powerful analytical tool that can serve to update inventory data in tropical Brazil and also to provide estimates for expected forest afforestation. The system has the capability of providing detailed outputs, which allows forest managers to consider merchandizing the clonal Eucalypt stands into multiple products. North Carolina State Univ, Dept Forestry & Environm Resources, 2820 Faucette Dr,Campus Box 8001, Raleigh, NC 27695 USA Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, 310 W Campus Dr,Campus Box 169, Blacksburg, VA 24061 USA Univ Fed Santa Catarina, Dept Forestry Agr & Biodivers, Campus Box 101,Rod Ulysses Gaboardi,Km 3, BR-89520000 Curitibanos, SC, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ,3780, BR-18610034 Botucatu, SP, Brazil Univ Sao Paulo, Dept Forest Sci, Ave Padua Dias,11, BR-13418900 Piracicaba, SP, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ,3780, BR-18610034 Botucatu, SP, Brazil CNPq: 249979/2013-6

Made available in DSpace on 2019-10-04T12:34:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Born Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jani Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Several approaches for modeling whole-stand survival or mortality have been reported in the literature, although this component is often times neglected for clonal eucalypt stands in Brazil. In addition, the traditional form for projecting whole-stand survival appears incomplete for clonal eucalypt stands, since this tree species is highly sensitive to lack of water in the environment. Consequently, this study aimed to define the best approach to estimate whole-stand survival in clonal eucalypt stands and to develop a new approach for modeling whole-stand survival as a function of cumulative soil water deficit. Remeasurement of sixteen research sites composed the database used in this study. At each research site, the same eleven eucalypt clones were planted in single block plots, which results in a total of 176 plots distributed across Brazil. Two traditional approaches (two-step approach and direct estimation) were tested for modeling whole-stand survival. Additionally a new approach that replaces the age term by cumulative soil water deficit (cumulative SWD) was compared to the best selected traditional approach to estimate whole-stand survival in clonal eucalypt stands. The direct projection approach of whole-stand survival displayed better results when compared to the two-step approach. In addition, the replacement of age by cumulative SWD in the direct estimation approach allowed for an increase in the explanatory ability of the developed difference model. The newly developed difference model employing the direct estimation approach constrained by cumulative SWD ensures that the environmental stress effect is reflected on the survival of clonal eucalypt stands over time, and it is more biologically sound for extrapolation purposes. North Carolina State Univ, Dept Forestry & Environm Resources, 2820 Faucette Dr,Campus Box 8001, Raleigh, NC 27695 USA Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, 310 W Campus Dr,Campus Box 169, Blacksburg, VA 24061 USA Forestry Sci & Res Inst, Via Comendador Pedro Morganti, BR-13415000 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ,3780, BR-18610034 Botucatu, SP, Brazil Univ Sao Paulo, Dept Forest Sci, Ave Padua Dias,11, BR-13418900 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ,3780, BR-18610034 Botucatu, SP, Brazil CNPq: 249979/2013-6

Made available in DSpace on 2021-06-25T10:30:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Understanding the processes that underlie the effects of tree diversity on primary production is of foremost importance to enhance climate change mitigation by tropical forests. Here, we investigated the effects of tree diversity on light interception over space and time in two tropical tree experiments, located in Panama—Sardinilla site (monocultures to 18-species mixtures), and in Brazil—Anhembi site (20- to 114-species mixtures). We assessed intercepted photosynthetically active radiation (iPAR) over horizontal grids and vertical transects (up to 5 m high in Sardinilla and up to 4 m high in Anhembi), in plots containing different richness levels and combinations of species. Light interception increased from monocultures to 5-species mixtures in Sardinilla and from 20- to 114-species mixtures in Anhembi (during the dry season). At the Sardinilla site, five-species mixtures showed iPAR comparable to the best performing monocultures, despite substantial differences observed among monocultures. Diversity-iPAR relationships changed seasonally and were more pronounced during the dry season. Tree richness promoted a less variable temporal and spatial (i.e. both horizontal and vertical) distribution of light interception. Synthesis. High tree diversity (i.e. over a hundred species in mixture) maximizes the amount of light intercepted by the canopy in restored tropical forests through more even capture in space and time. Diversity-light interception relationships should be critically considered for designing cost-efficient large-scale tropical forest restoration programs. Department of Biological Sciences “Luiz de Queiroz” College of Agriculture University of São Paulo (ESALQ/USP) Department of Mathematics and Statistics Maynooth University CIRAD UMR Eco&Sols Eco&Sols Univ Montpellier CIRAD INRAE IRD Department of Forest Sciences “Luiz de Queiroz” College of Agriculture University of São Paulo (ESALQ/USP) Department of Biology McGill University Department of Statistics Federal University of Paraná Department of Forest Science São Paulo State University (UNESP) Department of Forest Science São Paulo State University (UNESP)

Made available in DSpace on 2022-04-28T17:20:25Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 French Space Study Center (CNES, TOSCA 2020 project) National Research Institute for Agriculture, Food, and the Environment (INRAE) Over the past two decades spaceborne LiDARsystems have gainedmomentumin the remote sensing community with their ability to accurately estimate canopy heights and aboveground biomass. This article aims at using the most recent global ecosystem dynamics investigation (GEDI) LiDAR system data to estimate the stand-scale dominant heights (H-dom), and stand volume (V) of Eucalyptus plantations in Brazil. These plantations provide a valuable case study due to the homogenous canopy cover and the availability of precise field measurements. Several linear and nonlinear regression models were used for the estimation of H-dom and V based on several GEDI metrics. H-dom and V estimation results showed that over low-slopped terrain the most accurate estimates of H-dom and V were obtained using the stepwise regression, with an root-mean-square error (RMSE) of 1.33m(R-2 of 0.93) and 24.39 m(3).ha(-1) (R-2 of 0.90) respectively. The principal metric explaining more than 87% and 84% of the variability (R-2) of H-dom and V was the metric representing the height above the ground at which 90% of the waveform energy occurs. Testing the postprocessed GEDI metric values issued from six available different processing algorithms showed that the accuracy on H-dom and V estimates is algorithm dependent, with a 16% observed increase in RMSE on both variables using algorithm a5 vs. a1. Finally, the choice to select the ground return from the last detected mode or the stronger of the last two modes could also affect the H-dom estimation accuracy with 12 cm RMSE decrease using the latter. Univ Montpellier, French Natl Res Inst Agr Food & Environm INRAE, AgroParisTech, CIRAD,CNRS,TETIS, F-34093 Montpellier, France UNESP, Fac Ciencias Agron, BR-18610034 Botucatu, SP, Brazil Suzano SA, BR-13465970 Limeira, Brazil Univ Montpellier, LISAH, Inst Agro, INRAE,IRD, F-34060 Montpellier, France IRD, CNRS, UPS, Ctr Study Biosphere Space,CNES,INRAE, F-31401 Toulouse, France CIRAD, UMR Eco & Sols, F-34398 Montpellier, France IRD, INRA, CIRAD, Eco & Sols, Montpellier, France Univ Montpellier, SupAgro, F-34060 Montpellier, France UNESP, Fac Ciencias Agron, BR-18610034 Botucatu, SP, Brazil

Made available in DSpace on 2020-12-12T01:32:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01 Clonal plantations of Eucalyptus are among the most productive forests in the world, with intensification of silviculture and genetic breeding doubling the wood mean annual increments over the past four decades. The TECHS Project demonstrated that even with intensive silviculture, wood production varies by more than two-fold across environmental gradients, and growth of highly selected clones differs by more than two-fold within a site. Wood production accounts for less than half of the photosynthesis of a forest, and we tested two hypotheses about the relation between wood production and the entire carbon balance for five genotypes across four of the TECHS sites, varying in temperature and water availability. We hypothesized that the influence of the environment on carbon fluxes and partitioning related to gross primary production would be consistent across genotypes. We also hypothesized that carbon flux and partitioning would be more sensitive to water stress than temperature. Annual average temperatures ranged from 18 to 27 °C, and annual rainfall ranged from about 600 to 1500 mm yr−1. Water stress was further tested by reduction in rainfall within sites using troughs to capture about 30% of incoming rain. The geographic gradient led to a six-fold range in wood net primary production during the two years of measurement (from age 1.5 to 3.5 years, the period of maximum current annual increment). Gross primary production (GPP) differed only by two-fold, highlighting very large differences among sites in partitioning: wood net primary production (NPP) accounted for 44% of GPP on sites with higher GPP, and only 34% of GPP on lower GPP sites. The average differences for wood NPP among clones was also large, with about half of the differences among clones relating to differences in GPP, and half to differences in the partitioning to wood NPP. The clones showed similar partitioning patterns across sites, supporting our first hypothesis. Differences across sites and clones in partitioning of GPP to wood NPP related inversely to belowground allocation. Belowground partitioning of carbon increased with increasing temperature and increasing water stress. Our second hypothesis was rejected, as patterns across sites related somewhat more strongly to temperature than to water stress. Overall, this ecophysiological investigation in the TECHS Project underscored the importance of understanding how carbon budgets differ across sites (even with intensive silviculture), and why clones can largely differ in wood production. Department of Forest Sciences Federal University of Lavras (UFLA) Department of Forest Soils and Environmental Sciences São Paulo State University (UNESP) Forestry Science and Research Institute (IPEF) School of Forestry Northern Arizona University Natural Resource Ecology Laboratory Colorado State University USDA Forest Service Rocky Mountain Research Station Klabin Telêmaco Borba International Paper Suzano Department of Forest Soils and Environmental Sciences São Paulo State University (UNESP)

Made available in DSpace on 2020-12-12T01:29:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-10-15 Phenotypic plasticity refers to the ability of a single genotype to express distinct phenotypes in response to the environment, a crucial feature for sessile organisms like forest trees, especially in a scenario of global climate change. Several studies show that epigenetic regulation plays an important role in this plastic adaptation response, driving the search for associations between natural epigenetic variation with environmental cues and phenotypic traits based on patterns of cytosine methylation. Clonally propagated trees across variable sites offer a robust system to control for the confounding effect of the background genetic variation among genotypes, allowing the analysis of epigenetic modifications in response to variable environments. In this study we investigated the overall patterns of epigenetic changes by the analysis of the genome-wide DNA methylation status based on high throughput MS-DArT-seq (Methyl Sensitive DArT-seq sequencing) of reduced genome complexity representations. We compared patterns of DNA methylation of biological replicates of leaf and xylem tissue samples of four commercially planted elite Eucalyptus grandis × Eucalyptus urophylla clones and one Eucalyptus urophylla in two contrasting sites in Brazil, and the association of these methylation patterns with the environments and growth traits. DNA sequence reads were mapped against the Eucalyptus grandis reference genome, counting and annotating differentially methylated sites. A total of 90,378 MS-DArT-seq sites were identified, the majority (~70%) located in genes and 10% in transposable elements. The distribution of methylation sites showed extensive variation between the five genotypes and the environments. Sets of methylation sites exclusive to each location were identified for each clone but no consistently shared epigenetic marks for all five clones were found across environments. Multiple correspondence analysis suggests a significant contribution of the genetic background on the distribution of methylation changes. We used a gene-environment association analysis to search for association of methylation patterns with growth traits. A total of 445 methylation sites across all 11 Eucalyptus chromosomes were found significantly associated with one or more of the three measured traits (total height, estimated volume and breast high diameter). The absence of clustered differentially methylated sites is consistent with the fact that complex growth traits are governed by a large number of loci of small effect across the entire genome suggesting that this same pattern will likely hold for what regards epigenetic marks. Department of Cell Biology University of Brasília Embrapa Genetic Resources and Biotechnology Department of Forest Sciences Federal University of Lavras – UFLA Department of Forest Science São Paulo State University – UNESP Department of Forestry and Environmental Resources – Suzano Universidade Católica de Brasília Department of Forest Science São Paulo State University – UNESP

Made available in DSpace on 2020-12-12T01:19:41Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-15 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) We examined the influence of stand density and genotype on transpiration and water use efficiency in high productivity plantations. Three widely planted Eucalyptus clones that differ in drought tolerance and productivity (E. urophylla, E. urophylla × E. grandis and E. grandis × E. camaldulensis, clones IP, B2 and C3, respectively) were measured at four densities (590, 1030, 1420, and 2950 trees ha−1). Over the 1-year study period (1.5–2.5 years after planting), individual biomass increment decreased with increasing density, from 21 kg tree−1 at 590 trees ha−1 to 6 kg tree−1 at 2950 trees ha−1. Stand increment typically follows the reverse pattern, increasing as density increases. This was the case for two clones (IP and B2), but stand increment was consistent across tree spacings for C3. Transpiration increased with density, from a low of 622 mm yr−1 to a high of 879 mm y−1. Some of the increased water use resulted from higher leaf area index at higher densities. The B2 clone transpired the most water on average, produced the greatest increment (23 Mg ha−1 yr−1 for 1030 trees ha−1), and produced the most wood L−1 transpiration (water use efficiency, 2.3 g biomass L−1). The clone C3 had the lowest increment (only 12 Mg ha−1 yr−1) because of the combination of low transpiration and low water use efficiency (only 1.5 g biomass L−1). Optimizing clone selection and silviculture for the combination of high yield and high water use efficiency may help reduce risks from drought as well as water conservation. Department of Forest Science Federal Rural University of Pernambuco USDA Forest Service Rocky Mountain Research Station Department of Forest Sciences University of São Paulo UNESP-FCA Department of Forest Sciences Federal University of Lavras UNESP-FCA

Made available in DSpace on 2020-12-12T01:16:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-05-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Universidade de São Paulo Differences in growth rates between Eucalyptus clones depend on differences in the acquisition of resources, and the efficiency of using resources to produce carbohydrates and grow wood. We examined differences in canopy structure, light interception, and light use efficiency for the 18 TECHS clones in a common garden experiment in Brazil. The degree of clumping within canopies varied substantially among clones, leading to large differences in both leaf area and light interception per unit of leaf area. Two methods of determining plot-level leaf area index (LP-80 and LAI-2000) were moderately well correlated (R2 = 0.4), but both methods underestimated actual leaf area index (determined by destructive sampling) by about one-third. Completely overcast sky conditions increased accuracy of leaf area estimates, reducing variation among measurements within plots and lowering the number of samples needed to obtain a given level of precision. Genotypes with high leaf area clumping also had higher leaf angle inclinations than genotypes with lower clumping. The apparent light interception coefficient (k) averaged 0.56 for the LP-80, and 0.47 for the LAI-2000. The range of k estimates differed by up to 2-fold among clones, underscoring the limited generality of light extinction coefficients. Light interception ranged from about 70 to 95% of incoming light, and leaf area index accounted for only 30% of the pattern in light interception among clones. Differences in stemwood production were influenced more strongly by clonal differences in efficiency of light use (stemwood production per unit of light intercepted) than by differences in leaf area or light interception. The efficiency of producing wood per unit of light intercepted spanned a two-fold range, with higher efficiencies for more productive clones. We suggest that production ecology studies focus more on measurements of light interception than on leaf area, avoiding issues about difficult-to-measure features of crown and canopy structures. The additional step of characterizing light use efficiency would also be very important. Department of Forest Sciences University of São Paulo Geplant Forest Technology Llc. School of Forestry Northern Arizona University Universidade Federal de Lavras Department of Forest Science São Paulo State University - UNESP Department of Forest Science São Paulo State University - UNESP

Made available in DSpace on 2020-12-12T02:36:23Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-15 Different ecophysiological models are used to predict the productivity of forest plantations worldwide. The Physiological Principles in Prediction Growth (3-PG) model has been successfully used for this purpose since 1997. In this study, the 3-PG model was parameterized and validated to predict the productivity of the most planted clonal eucalypts in Brazil (Eucalyptus urophylla) in different regions of the country and assess the attainable productivity of this same clone for a region little exploited for this plantations in the country. Through data collection carried out between 2012 and 2018, conducted in 36 sites distributed across an environmental gradient that spans over 3500 km in Brazil, it was possible to parameterize the 3-PG model using data that represent a portion of the soil and climate diversity of forest plantations in Brazil. We determined the initial biomass of the compartments (stem, leaf, and root), relationship between net and gross productivity, average wood density, maximum stem biomass for 1000 trees ha−1, maximum stomatal conductance, bark and branch fractions for the initial and mature age, specific leaf area for the initial and mature age, and allometric parameters at different ages. Considering the model initialization period, the initial age was defined at 12 months after planting and the final age was considered at 80 months. Model calibration was performed in four experimental sites (special sites for the calibration set), which correspond to the environmental diversities of the project, and model validation was performed by applying the setup of the model obtained in 10 other sites (regular sites for validation set) of the same experimental network. In all sites tested, estimates of basal area, diameter at breast height, leaf area index, and stem biomass agreed with the measured values. On average, the estimates of diameter and breast height were 4.91% higher than the observed measures, whereas the stem biomass estimates were 16.44% lower and the leaf area index was 26.22% lower; moreover, the estimates were overestimated for the first three years and underestimated in recent years. Overall, the model was able to capture the soil and climate differences for predicting E. urophylla clone productivity. Its application in a region not yet exploited for eucalypts plantations may help investors in the region select areas for acquisition, planting extensions, and extend production technologies. Department of Forest Soils and Environmental Sciences São Paulo State University-UNESP Department of Agronomy Rondônia Federal Institute, 76993-000 Colorado do Oeste Suzano SA Company Federal University of Lavras – UFLA, 37.200-000 Lavras Department of Forest Science Federal Rural University of Pernambuco – UFRPE Department of Forest Soils and Environmental Sciences São Paulo State University-UNESP

Increasing forest site productivity is a need. Land use conflicts, high land prices, or owners’ objectives, have motivated forest managers to apply more intensive silvicultural treatments to increase forest site productivity. Understanding how intensive silvicultural practices such as weed control and fertilization + weed control affect productivity will permit managers to select the best treatment to increase it. Our objectives were: (1) to estimate the gap between current and attainable productivity of Eucalyptus plantations and (2) to determine the effect of treatment on light use and light use efficiency. To estimate the gap between current and attainable productivity, we established 53 pairs of plots, which were measured for two years. Each pair consisted of a control plot, which received the management regime that is regularly applied to the stands, and a treated plot, which received intensive silvicultural treatment (fertilization + weed control) in addition to the operational management applied to the control plots. At 25% of the sites, a third plot (weed control only) was established. Stem biomass growth in the control and treated plots was 12.4 and 14.8 Mg ha−1 yr−1, respectively. We found significant differences in light use between the control and treated plots, i.e., averages of 1344 MJ m−2 yr−1 and 1406 MJ m−2 yr−1, respectively, representing a 4.6% increase. The increase in light use efficiency (LUE) was higher and reached 20%. On average, the control plots had a LUE of 0.9 g of dry mass (DM)/MJ compared with 1.10 g DM/MJ for the treated plots. There is a considerable opportunity to increase forest productivity through fertilization, and it may be possible to obtain greater gains than those observed in this study. This information is important to estimate the expected responses to intensive silviculture and will help to decide where silvicultural treatments should be applied to maximize the gains obtained from the investment.

International audience; Evapotranspiration and energy partitioning are complex to estimate because they result from the interaction of many different processes, especially in multi-species and multi-strata ecosystems. We used MAESPA model, a mechanistic, 3D model of coupled radiative transfer, photosynthesis, and balances of energy and water, to simulate the partitioning of energy and evapotranspiration in homogeneous tree plantations, as well as in heterogeneous multi-species, multi-strata agroforests with diverse spatial scales and management schemes. The MAESPA model was modified to add (1) calculation of foliage surface water evaporation at the voxel scale; (2) computation of an average within-canopy air temperature and vapour pressure; and (3) use of (1) and (2) in iterative calculations of soil and leaf temperatures to close ecosystem-level energy balances. We tested MAESPA model simulations on a simple monospecific Eucalyptus stand in Brazil, and also in two complex, heterogeneous Coffea agroforests in Costa Rica. MAESPA satisfactorily simulated the daily and seasonal dynamics of net radiation (RMSE = 29.6 and 28.4 W m−2; R2 = 0.99 and 0.99 for Eucalyptus and Coffea sites respectively) and its partitioning between latent-(RMSE = 68.1 and 37.2 W m−2; R2 = 0.87 and 0.85) and sensible-energy (RMSE = 54.6 and 45.8 W m−2; R2 = 0.57 and 0.88) over a one-year simulation at half-hourly time-step. After validation, we use the modified MAESPA to calculate partitioning of evapotranspiration and energy between plants and soil in the above-mentioned agro-ecosystems. In the Eucalyptus plantation, 95% of the outgoing energy was emitted as latent-heat, while the Coffea agroforestry system’s partitioning between sensible and latent-heat fluxes was roughly equal. We conclude that MAESPA process-based model has an appropriate balance of detail, accuracy, and computational speed to be applicable to simple or complex forest ecosystems and at different scales for energy and evapotranspiration partitioning.

Made available in DSpace on 2018-11-26T17:42:01Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-12-01 Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Born Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo - Brazil Sao Paulo State University - Brazil Federal University of Lavras - Brazil Federal University of Rio Grande do Norte - Brazil Colorado State University - USA North Carolina State University - USA USDA Forest Service Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Intensively managed plantations account for 1.5% of the world's forests, but they meet one-third of the demand for wood products. Eucalyptus plantations are among the most productive, with rates of growth depending heavily on genetics, silviculture, and climate. The TECHS Project examines productivity at 36 locations across a 3500 km gradient from Brazil to Uruguay, testing the interacting influences of genetics, temperature and precipitation on stemwood production. Across all sites and genotypes, stemwood production in the middle of the 6 year rotation (the peak period of growth) averaged 22 Mg ha(-1) yr(-1). Production varied by fivefold across sites, and by about 2-fold among genotypes within each site. The best clones at each location grew 1.5-4 Mg ha(-1) yr(-1) more than the average for all clones, underscoring the importance of matching genotypes to local site conditions. Contrary to patterns for natural forests across geographic gradients, Eucalyptus production declined with increasing temperature, dropping by 2.5 Mg ha(-1) yr(-1) for a 1 degrees C temperature increase. The temperature effect was likely driven in part by the geographic covariance of temperature and rainfall, as rainfall tended to decline by 78 mm yr(-1) for each 1 degrees C increase in temperature. Stemwood production increased an average of 1.5 Mg ha(-1) yr(-1) for each 100 mm yr(-1) increase in precipitation, but when the covariation of temperature and precipitation were included the apparent influence of precipitation declined to 0.4 Mg ha(-1) yr(-1) for each 100 mm yr(-1) increase in precipitation. Future results will determine if within-site reductions in ambient rainfall have the same apparent influences as the rainfall pattern across the geographic gradient, as well as quantifying the importance of insects and pests in affecting growth. The supply of wood from intensively managed plantations will be strongly influenced by both temperature and precipitation at plantation locations, and with changing climates. No Arizona Univ, Sch Forestry, Flagstaff, AZ 86011 USA Swedish Univ Agr Sci, Dept Forest Ecol & Management, SE-90183 Umea, Sweden Fed Univ Santa Catarina UFSC, BR-89520000 Curitibanos, SC, Brazil Inst Pesquisas & Estudos Florestais, Via Comendador Pedro Morganti,3500 Bairro Monte A, Piracicaba, SP, Brazil Univ Sao Paulo, Dept Forest Sci, BR-13400 Piracicaba, SP, Brazil Sao Paulo State Univ, Dept Forest Sci, BR-18600 Botucatu, SP, Brazil Sao Paulo State Univ, Dept Forest Sci, BR-18600 Botucatu, SP, Brazil

[Departement_IRSTEA]Territoires [TR1_IRSTEA]SYNERGIE [Axe_IRSTEA]TETIS-ATTOS; International audience; Finding suitable models of canopy reflectance in forward simulation mode is a prerequisite for their use in inverse mode to characterize canopy variables of interest, such as leaf area index (LAI) or chlorophyll content. In this study, the accuracy of the three-dimensional reflectance model DART (Discrete Anisotropic Radiative Transfer) was assessed for canopies of different genotypes of Eucalyptus, having distinct biophysical and biochemical characteristics, to improve the knowledge on how these characteristics are influencing the reflectance signal as measured by passive orbital sensors. The first step was to test the model suitability to simulate reflectance images in the visible and near infrared. We parameterized DART model using extensive measurements from Eucalyptus plantations including 16 contrasted genotypes. Forest inventories were conducted and leaf, bark, and forest floor optical properties were measured. Simulation accuracy was evaluated by comparing the mean top of canopy (TOC) bidirectional reflectance of DART with TOC reflectance extracted from a Pleiades very high resolution satellite image. Results showed a good performance of DART with mean reflectance absolute error lower than 2%. Intergenotype reflectance variability was correctly simulated, but the model did not succeed at catching the slight spatial variation for a given genotype, excepted when large gaps appeared due to tree mortality. The second step consisted of sensitivity analysis to explore which biochemical or biophysical characteristics influenced more the canopy reflectance between genotypes. Perspectives for using DART model in inversion mode in these ecosystems were discussed. [ABSTRACT FROM PUBLISHER]

Although Brazil is predominantly a tropical country, frosts are observed with relative high frequency in the Center-Southern states of the country, affecting mainly agriculture, forestry, and human activities. Therefore, information about the frost climatology is of high importance for planning of these activities. Based on that, the aims of the present study were to develop monthly meteorological (F MET) and agronomic (F AGR) frost day models, based on minimum shelter air temperature (T MN), in order to characterize the temporal and spatial frost days variability in Center-Southern Brazil. Daily minimum air temperature data from 244 weather stations distributed across the study area were used, being 195 for developing the models and 49 for validating them. Multivariate regression models were obtained to estimate the monthly T MN, once the frost day models were based on this variable. All T MN regression models were statistically significant (p

The goals of this study were to identify and group three eucalyptus clones, each under coppice and clear-cut management regimes, into two or more groups based on similar growth rates; and fit a site index equation as a function of rainfall variables for each group to evaluate how different groups were impacted by climatic variation. The database came from the Continuous Forest Inventory (CFI) and weather stations. The CFI was conducted between 1994 and 2012, with climatic data also being gathered for the same period. The study area was managed by clear-cut and coppice regimes, with 126 and 72 CFI plots, respectively. The relationship between clones, management regimes and stand age with annual dominant height growth was assessed by linear mixed effects modeling. Ridge regression was applied for fitting each group as a function of the rainfall variables. Finally, ordinary Kriging was applied for each of the rainfall variables in the study area. Then, site index equations were applied to the generated maps enabling the observation of their pattern throughout the study area as well as their evaluation under a pessimistic climatic scenario. Three groups were defined, since each clone exhibited similar growth behavior under either management regimes; however, the 3 clones differ among each other. A significant reduction in the annual dominant height growth over time was observed for all 3 clones. Ridge regressions afforded good accuracy and equations with sound biological behavior. Applying the fitted site index equations to the maps of precipitation and rainy days enabled the definition of the most appropriate clone to be planted throughout the area. Site quality as a function of rainfall variables could be an important tool to better enable silvicultural planning, since it provides estimates of the site index and also enables the incorporation of short-term climate change.

The choice of planting density and tree genotype are basic decisions when establishing a forest stand. Understanding the interaction between planting density and genotype, and their relationship with biomass production and potential water stress, is crucial as forest managers are faced with a changing climate. However, few studies have investigated this relationship, especially in areas with highly productive forests. This study aimed to determine the interaction between biomass production and leaf water potential, as a surrogate of potential water stress, in different clonal Eucalyptus genotypes across a range of planting densities. Four clones (two clones of E. urophylla × E. grandis, one clone of E. urophylla, and one clone of E. grandis × E. camaldulensis) and four planting densities (ranging from 591 to 2 949 trees ha−1) were evaluated in an experimental stand in south-eastern Brazil. Biomass production was estimated 2.5 years after planting and predawn (ψpd) and midday (ψmd) leaf water potential wer...

Made available in DSpace on 2019-10-04T12:35:59Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-03-01 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Petrobras Company Forestry Science and Research Institute (IPEF) Anhembi Experimental Station of Forest Sciences of the University of Sao Paulo IN-SYLVA French network Maximizing initial aboveground woody biomass (AGB) accumulation in order to obtain early payments for carbon stocking is essential for the financial viability of reforestation programs fostered by climate mitigation efforts. Intensive silviculture, i.e., silviculture traditionally used in commercial forestry to maximize productivity and gains, has recently been advocated as a promising approach to enhance AGB accumulation in restoration plantations. However, this approach may hamper natural forest regeneration and ecological succession due to high competition between colonizing plants and planted trees. We investigated the impacts of different silvicultural treatments applied to restoration plantations with 20 native tree species on AGB accumulation and spontaneous regeneration of native woody species in an experiment set up in the Atlantic Forest of Brazil. Intensive silviculture demonstrated a remarkable potential to enhance AGB accumulation in restoration plantations by increasing up to three times the AGB of tree stands (from similar to 25 to 75 Mg/ha in the 12th year). Intensive fertilization/weed control enhanced AGB accumulation, while higher tree density and the proportion of pioneers did not have a significant effect on AGB over the time. In spite of higher costs (cost increase of 13-19%), the cost-effectiveness for AGB accumulation of intensive silviculture was comparable to that of traditional silviculture applied to restoration (US$50-100/Mg AGB for 3 x 2 m spacing). Contrary to our expectations, we did not find a trade-off between AGB accumulation by planted trees and the spontaneous regeneration of tree species, since intensive silviculture enhanced the regeneration of both planted (total of 12 species) and colonizing woody species (total of 30 species) in the plantation understory. Specifically, a strong association was found between AGB stocks and the abundance and richness of colonizing species, a vast majority of which (90% of species and 95% of individuals) were dispersed by animals. We report a case of positive correlation between AGB stocking and woody species regeneration in the restoration of the Atlantic Forest. Fostering the establishment and maintenance of restoration tree plantations can, in some cases, be a win-win strategy for climate mitigation and biodiversity conservation in human-modified tropical landscapes. Univ Sao Paulo, Dept Forest Sci, Luiz de Queiroz Coll Agr, Ave Padua Dias 11, BR-13418900 Piracicaba, SP, Brazil Univ Fed Santa Catarina, BR-89520000 Curitibanos, SC, Brazil Sao Paulo State Univ, Dept Forest Sci, BR-19600 Botucatu, SP, Brazil UMR Eco & Sols, CIRAD, F-34060 Montpellier, France Univ Montpellier, Montpellier SupAgro, CIRAD, INRA,IRD,Eco & Sols, F-34060 Montpellier, France Sao Paulo State Univ, Dept Forest Sci, BR-19600 Botucatu, SP, Brazil CNPq: 304817/2015-5 FAPESP: 2012/05814-3 FAPESP: 2013/50718-5

Made available in DSpace on 2019-10-04T12:34:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-01-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The research objective of this paper was to group eleven widely planted eucalypt clones based on their volume yield pattern by assessing how climatic variation impacts their productivity in tropical Brazil. A total of 187 plots evenly distributed across eleven clones and 17 sites (from Parana to Para State) were used. Plot measurements were carried out every six months (from 2013 to 2017) to evaluate eucalyptus growth. Since the year of plot establishment differs across the sites, volumes of all the plots and sites were standardized at a common age of 5 years. Clonal grouping analysis was performed based on the common age for volume yields using a new approach, which consisted of three steps: (1) create general groups based on testing of the slope coefficient, which was applied to every clonal-specific regression with volume yield as a function of annual water deficit index (WDI); (2) split each general group using volume yield deviation computations into subgroups of high and low productivity; (3) apply linear mixed effects models for every subgroup in order to confirm the non-existence of statistical difference among the volume yield of the clones. Statistical tests showed satisfactory yield estimates at the common age of 5 years. Clonal grouping revealed the identification of four groups (A: high productivity and non-sensitive to climate variation, B: high productivity and sensitive to climate variation, C: low productivity and sensitive to climate variation, D: low productivity and non-sensitive to climate variation). The volume yield of the Clonal group B was detected to be the most impacted by annual water deficit index variation, followed by clonal groups C, A and D. The findings of the study highlighted the utility of the proposed approach for grouping clones. Group identification and detection of the climatic impact on yield patterns was evaluated as a measure to increase site-specific productivity. North Carolina State Univ, Dept Forestry & Environm Resources, 2820 Faucette Dr,Campus Box 8001, Raleigh, NC 27695 USA Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, 310 W Campus Dr,Campus Box 169, Blacksburg, VA 24061 USA Univ Fed Santa Catarina, Dept Forestry Agr & Biodivers, Campus Box 101,Rod Ulysses Gaboardi,Km 3, BR-89520000 Curitibanos, SC, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ,3780, BR-18610034 Botucatu, SP, Brazil Univ Sao Paulo, Dept Forest Sci, Ave Padua Dias,11, BR-13418900 Sao Paulo, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ,3780, BR-18610034 Botucatu, SP, Brazil CNPq: 249979/2013-6

Made available in DSpace on 2019-10-06T16:31:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2019-09-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Climate changes will increase the probability of drought, which is likely to dramatically increase tree mortality. The capacity of trees to withdraw water in deep soil layers is an important trait likely to account for tree survival over prolonged droughts. Our study aimed to gain insight into the maximum distance from the trunk where Eucalyptus fine roots take up water and mobile nutrients in deep sandy soils during dry periods. NO3 −-15N was injected in the soil at the end of the rainy season in commercial Eucalyptus stands planted with the same E. urophylla × E. grandis clone. The 15N tracer was applied in the middle of the inter-row (replicated in 3 plots): at 5 depths (from 0.1 to 6 m)at age 0.6 year, at 4 depths (from 0.1 to 9 m)at age 1.2 years, at 5 depths (from 0.1 to 12 m)at age 2.2 years, and at 6 depths (from 0.1 to 15 m)at age 6.4 years. δ15N was determined in leaves sampled in dominant and suppressed trees at different distances from each injection area, 4–5 months after NO3 −-15N injection (after the dry season). While dominant trees took up NO3 −-15N down to a depth of 6 m between 7 and 12 months after planting, the maximum depth of NO3 −-15N uptake for suppressed trees was between 3 and 4.5 m. From 1.5 to 6 years after planting, a foliar enrichment in 15N was mainly detected when the NO3 −-15N tracer was injected in the upper soil layers and only for a few trees at a depth of 6 m. Most of the uptake of 15N occurred within 2 m of horizontal distance from the injection site, whatever tree age and tree social status. Low amounts of NO3 −-15N were taken up for injection sites located between 2 m and 5 m from the trunk, and 15N uptake was never detected at horizontal distances greater than 6 m from the trunk. Eucalyptus fine roots can take up nitrates at depths between 6 and 8 m the first year after planting. However, the NO3 −-15N tracer injected at a depth of 6 m was only taken up by dominant trees and a 15N foliar enrichment of suppressed trees was only detected when the tracer was injected in the upper 3 m. Fertilizers must be applied within 2 m of the trunks in Eucalyptus plantations to be taken up by all trees, regardless of their social status. When fertilizations are concentrated the first months after planting in sandy soils, nutrient leaching in deep layers might increase the heterogeneity of the stands since mobile nutrients could only be taken up by dominant trees. Universidade Estadual Paulista (Unesp) Faculdade de Ciências Agronômicas CIRAD UMR Eco&Sols Eco&Sols CIRAD INRA IRD Montpellier SupAgro University of Montpellier ESALQ Universidade de São Paulo Universidade Estadual Paulista (Unesp) Centro de Isótopos Estáveis Suzano SA Company Universidade Estadual Paulista (Unesp) Faculdade de Ciências Agronômicas Universidade Estadual Paulista (Unesp) Centro de Isótopos Estáveis FAPESP: 2015/25946-0

Made available in DSpace on 2020-12-12T01:33:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-11-01 International Paper Cross-site patterns for multiple sites tend to be more broadly applicable and more useful for constructing and constraining models. We examined cross-site patterns of Eucalyptus plantation response to water supply (including irrigation and 1/3 precipitation removal), mean annual temperature (MAT), vapor pressure deficit during the daytime (VPD), and nutrient addition in eight sites from the Brazil Eucalyptus Productivity Project (BEPP). Mean annual increment (MAI) for all treatments and sites varied from 12.7 to 37.3 Mg ha−1 yr−1 across a 1400 km latitudinal gradient where annual precipitation varied from 940 to 1430 mm yr−1. MAI varied with water added across all sites, with a near linear increase of 1.42 Mg ha−1 yr−1 per 100 mm yr−1 between 640 and 1800 mm yr−1, a MAI plateau of 30.8 Mg ha−1 yr−1 at ~2000 mm yr−1, then decreasing to MAI of 27.2 Mg ha−1 yr−1 at 3060 mm yr−1. Including MAT with the water response showed that MAI decreased at 1.23 Mg ha−1 yr−1 per °C. For the natural precipitation treatments, MAI decreased at 2.52 Mg ha−1 yr−1 per °C, comparable to that for the much broader TECHS Project (Binkley et al., 2020). MAI was not related to temperature for the irrigation treatments, suggesting that some or all of the response of MAI to temperature is related to water supply. The difference between the biomass of the irrigation treatments and that of natural precipitation treatment slowed its increase or stopped increasing at age 30–60 months for five of the eight sites, but increased through the study duration for the other three sites. The difference in biomass between the fertilization and no fertilization treatments increased throughout the study for two sites. Three- and six-month growth was generally unrelated prior 3–12 month weather. Age-related decline was observed for all of the treatments at four of the eight sites. These cross-site comparisons affirm that water supply is the key resource determining levels of plantation productivity in Brazil and that individual site studies are inadequate for understanding many key responses. Department of Ecosystem Science & Sustainability Colorado State University USDA Forest Service Rocky Mountain Research Station Department of Forest Science São Paulo State University – UNESP Forestry Science and Research Institute (IPEF) School of Forestry Northern Arizona University Department of Forest Science São Paulo State University – UNESP

Made available in DSpace on 2020-12-10T19:58:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-15 Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Anglo American Arauco Arborgen ArcelorMittal Cenibra CMPC Comigo Copener Duratex Eldorado Fazenda Campo Bom Fibria Florestal Itaquari Forestal Oriental Gerdau GMR International Paper Jari Klabin Lwarcel Montes del Plata Plantar Rigesa Suzano Vallourec Veracel University of Sao Paulo Sao Paulo State University Federal University of Lavras Federal University of Rio Grande do Norte Colorado State University North Carolina State University USDA Forest Service Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Growth models have been applied to assess the growth potential for areas without previous forest plantation records and to update forest inventory when commercial stands have been planted. However, there is a lack of growth models capable of incorporating environmental variables for updating forest inventories and recomputing site quality throughout Brazil. Consequently, this research aimed to deliver a compatible set of prediction and projection growth equations with parameters refined by environmental variables. The dataset used through this study is composed of remeasurement information of 16 research sites in Brazil. At each site, the same eleven eucalypt clones were planted in single block plots. Extra block plots were also installed in 14 sites to evaluate eucalyptus growth under drier climate scenarios. Four different competing model forms were tested. A common parameter of the best compatible set of growth equations was refined to test the magnitude of the environment effect on the prediction and projections of dominant height/site index in clonal eucalypt stands in Brazil. The compatible set of Chapman-Richards growth equations displayed the most accurate estimates of dominant height for clonal eucalypt plantations in Brazil. The common asymptote parameters between the growth models were refined as a function of annual soil water deficit (SWD), and a gain in accuracy of the projected and predicted dominant height estimates was observed. It is relevant to highlight that the developed set of growth equations possesses the ability to make short-, medium- and long-term predictions and projections with more assuredness about the biological behavior and its soundness. This feature ensures accurate estimation of site-specific growth curves. North Carolina State Univ, Dept Forestry & Environm Resources, 2820 Faucette Dr,Campus Box 8001, Raleigh, NC 27695 USA Univ Fed Lavras, LEMAF, Dept Forest Sci, Campus Univ,Campus Box 3037, BR-37200000 Lavras, MG, Brazil Virginia Polytech Inst & State Univ, Dept Forest Resources & Environm Conservat, 310 W Campus Dr,Campus Box 169, Blacksburg, VA 24061 USA Forestry Sci & Res Inst, Via Comendador Pedro Morganti 3500, BR-13415000 Piracicab, SP, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ 3780, BR-18610034 Botucatu, SP, Brazil Univ Sao Paulo, Dept Forest Sci, Ave Padua Dias 11, BR-13418900 Piracicaba, SP, Brazil State Univ Sao Paulo, Dept Forest Sci, Ave Univ 3780, BR-18610034 Botucatu, SP, Brazil CNPq: 249979/2013-6

Made available in DSpace on 2020-12-12T01:20:50Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-06-15 High stocking short rotation plantations provide high yields for bioenergy use and have been adopted worldwide, especially in tropical areas. This silvicultural approach might alter ecosystem water balances compared with lower stocking, longer rotation practices. The sensitivity of water balance to stocking might also differ among genotypes. We evaluated the primary components of ecosystem water balance (transpiration - Et, canopy interception - Ei, soil evaporation – Es) for two hybrid clones that differ in drought tolerance and productivity (E. urophylla × E. grandis, Clone B2 and E.grandis × E.camaldulensis, Clone C3) planted in stockings ranging from 590 to 2,950 tree ha.-1 in a tropical region in Brazil. On a monthly time step, all water balance components of the two clones were largely related to the seasonality of rainfall, where the wet season represented 73% of the total rainfall, these processes corresponded on average to 76, 75, 67 and 70% of annual canopy interception, soil evaporation, transpiration and evapotranspiration (ET), respectively. For both clones, temperature (R2 = 0.32) and precipitation (R2 > 0.76) explained evapotranspiration responses while adding stocking as a second independent variable slightly improving the model for clone B2 but no improvement was detected for clone C3. When scaling up the monthly data to yearly analyses, all water balance components responded strongly to tree stocking for both clones during the two years of measurements (1.7 to 3.7 years-old). Annual transpiration rose linearly with stocking for the clone B2, rising from 550 mm yr−1 up to 1,039 mm yr−1, corresponding to 53–100% of precipitation (P). The clone C3 showed a much weaker influence of stocking on transpiration, rising only from 550 mm yr−1 at low stocking to 650 mm yr−1 at high stocking (53–63% of P). Canopy interception rose from about 230 mm yr−1 at low stocking to 300 mm yr−1 at high stocking, with little difference between the clones, ranging from 21 to 30% of P. Evaporation from the soil decreased with increased stocking for both clones and represented an average of 20–12% of P from lowest to highest stocking. Total evapotranspiration (ET – sum of Et, Ei and Es) was about 1,000 to 1,050 mm yr−1 at low-to-moderate stockings of both clones, but the less-drought tolerant clone B2 showed substantially higher total evapotranspiration at high stocking (2,900 mm yr−1) compared to the clone C3 (2300 mm yr−1). The difference between precipitation and evapotranspiration (the overall ecosystem water balance) declined with increasing stocking, dropping below 0 at stockings higher than 1,030 tree ha−1 for both clones. High stocking in highly productive Eucalyptus plantations may be less sustainable across multiple rotations, since any deficit in the ecosystem water balance would need to come from longer-term soil water storage. Our results indicate that both genetics and tree stocking can be used as silviculture tools to manage the sustainably of short rotation forest plantations in the face of climate change. Department of Forest Science Federal Rural University of Pernambuco USDA Forest Service Rocky Mountain Research Station, Fort Collins UNESP-FCA Department of Forest Sciences University of São Paulo UNESP-FCA

Made available in DSpace on 2020-12-12T01:16:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-04-15 Colorado State University North Carolina State University Universidade Federal de Lavras Universidade Federal do Rio Grande do Norte U.S. Forest Service Universidade de São Paulo The TECHS project spanned a 3500 km gradient from the Amazon to Uruguay, examining the influence of stresses from temperature and water supply on clonal plantations of Eucalyptus, with and without rain reduction, and across a stocking gradient. The whole-rotation mean annual increment (MAI) showed a humped pattern in relation to temperature, rising from about 18 Mg ha−1 yr−1 of stemwood production when mean annual temperatures were near 16 °C, to 27 Mg ha−1 yr−1 at 20 °C, and then falling to less than 15 Mg ha−1 yr−1 above 24 °C. The age trend in growth showed a steeper initial rise in the warmer tropical sites (reaching a peak current annual increment, CAI, of 27 Mg ha−1 yr−1, at age 2–3 years), but the slower early growth in the cooler subtropical sites had a higher peak (CAI of 32 Mg ha−1 yr−1, at 4 years) and slower decline, giving 15% higher MAI for the cooler region. Whole-rotation MAI declined by about 2.2 Mg ha−1 yr−1 for each 1 °C increase in temperature (in the range between 19.5 and 23.5 °C), and MAI declined by 0.5 Mg ha−1 yr−1 for each 100 mm yr−1 decline in rain. The effect of reducing ambient rain was also a loss of 0.5 Mg ha−1 yr−1 for each 100 mm yr−1 reduction in rain, though the effect was small on low productivity sites (

Engenheiro Florestal da Fibria Celulose S/A, Rod. General Euryale Jesus Zerbini, s/n - Sao Silvestre

We examined the change in spatial structures of Eucalyptus plantations across different types of silvicultural treatments over a full rotation. Clonal and seed-origin Eucalyptus plots applied with differing levels of fertilization (high vs. traditional) and irrigation (irrigated vs. non-irrigated) treatments were investigated. Additionally, for the clonal plots, uniform vs. heterogeneous stand structure treatments were created using staggered planting dates. The heterogeneous structure of the clonal plots aimed to mimic the seed-origin plots. Spatial structures were characterized by assessing the spatial autocorrelations of diameters, heights, and biomass. We also applied two distance-based neighborhood structures to look at the degree of change in spatial autocorrelations with different numbers of neighboring trees being defined as neighbors. The results suggest that spatial autocorrelations of diameters, heights, and biomass of Eucalyptus plantations were mostly insignificant at an alpha level of 0.05 over the rotation. However, spatial autocorrelations in most plots after the middle of the rotation were predominantly negative, indicating the occurrence of size differences among neighboring trees. In particular, general declining patterns from positive to negative spatial autocorrelations in diameters and biomass, except for plots with the heterogeneous stand structures, were noted at plots treated with high levels of fertilizer. This suggests that high fertilization may have influenced the realizations of microsite effects in the early stage of stand development. General trends in spatial autocorrelations between the two neighborhood structures considered were mostly similar except for several plots differing in intensities of spatial autocorrelations over the rotation.

A nutrient dose and application frequency study was installed in Eucalyptus grandis stands at six sites in the Colombian Andes to examine three hypotheses: (1) individual sites have different treatment responses (there is a significant site effect); (2) the relationship between volume growth response and applied nitrogen is not linear (there is an optimal amount of applied nitrogen beyond which growth improvements would be small); and (3) application frequency does not affect response if the cumulative dose applied is equivalent (there is no frequency effect). Nitrogen, phosphorus and boron were applied at a 1.0:0.1:0.005 ratio, where nitrogen rates ranged from 0 to 250 kg ha−1 and application frequency was 6, 12, 24 or 36 months. Fertilization began when trees were 11–24 months old and we examined volume growth response three years after study initiation when the maximum cumulative nitrogen application reached 720 kg ha−1. There was a significant site effect: two sites were responsive and four were non-responsive to treatment. At the two responsive sites, the relationship between volume growth response and applied nitrogen was not linear. Three years after treatment initiation, the maximum absolute response was 142 m3 ha−1 (91% increase) and 116 m3 ha−1 (56% increase) for Sites 1 and 4, respectively. Sites 1 and 4 reached maximum volume response at cumulative nitrogen doses of 360 and 480 kg ha−1, respectively. Tests that compared different nitrogen application rates and frequencies to achieve the same cumulative dose were not significantly different except for one test at Site 4 where the volume growth response to three applications of 180 kg nitrogen ha−1 was 58% greater than the response to six applications of 90 kg ha−1.

Deforestation for urbanization and agriculture expansion drastically reduced the area of the Atlantic forest biome in Brazil. To reverse this process, rehabilitating degraded lands, restoration plantations with native tree species show significant potential to rebuild the forest habitat and promoting carbon sequestration. High input silviculture (intensive fertilization and weed control), similar to those applied in commercial production forest plantations can increase productivity, accelerating forest restoration process. We evaluated the effects of two contrasting silvicultural systems, “traditional” (based on common silviculture of forest reforestation in Brazil – low input) and “intensive” (based on commercial plantations – high input) on carbon (C) stocks of a restoration plantation. We also compared the plantations with a mature forest remnant. Six years after planting, forest C stock (coarse roots and aboveground biomass) under intensive silviculture reached 23.3 Mg C ha−1, more than 3-fold the stock under traditional silviculture (6.9 Mg C ha−1). Under both silvicultural systems, soil showed constant C stock (average of 33 Mg C ha−1). The C accumulation in biomass with intensive silviculture reached 12.8% of that stored in the mature forest (181.5 Mg C ha−1), compared with just 3.8% for traditional silviculture. Intensive silviculture provided nutrients and reduced competition with weeds, increasing growth and carbon sequestration. Forest plantations aiming at restoration and also carbon sequestration are practicable, and are highly responsive to intensive silviculture.

Drought stress promotes biochemical and physiological alterations in plant metabolism that limit growth and yield. This study investigated the accumulation of γ-aminobutyric acid (GABA) in plant tissue, the stomatal conductance (gs) and changes in leaf anatomy in Eucalyptus following drought stress situation. In this study, eight Eucalyptus clones were evaluated under normal water supply (control) and drought stress conditions (stress). For the control treatment, plants were irrigated every day with an automated system until the soil was saturated, and for the stress treatment, drought stress was imposed by non-irrigation of plants, and pots were covered using plastic sheeting to avoid rainfall and humidity. This study has shown that: (1) all clones decreased gs with increasing vapor pressure deficit (D) in both treatments. All plastics and drought-tolerant clones (except GG) presented lower stomatal sensitivity to D under stress conditions than drought-sensitive clones; (2) GABA concentrations increased fast after drought stress, but we could not find correlation with these changes and resistance to water stress; and (3) all clones increased the number of stomata and reduced leaf thickness after water stress. The finding is that GABA is a fast stress-signaling molecule in Eucalyptus, but the response of gs to D is a best physiological variable to differentiate drought-tolerant and drought-sensitive Eucalyptus clones.

The Brazilian Atlantic forest is considered one of the world's biodiversity conservation hotspot. Today there is less than ten percent remaining. Therefore it is necessary to restore these ecosystems. There are many ways of achieving restoration's main goals, but there is a lack of ecological studies that analyzes tree species richness as a variable. Thus, this study's goal is to investigate if there is a difference between a forest restoration in a gradient of tree species richness that varies from 20, 60 to 120 species, by using the litterfall as an indicator. Every month, for one year the forest litter was collected from litter traps that were previously installed. Results revealed that stands produced litterfall by the increasing gradient of species was of 5,370, 5,909 and 6,432 kg ha-1 yr-1. The statistical analyses revealed no significant difference among them. Therefore this six-year-old forest restoration plantation shows no difference on the litter production by the tree species richness., El bosque atlántico brasileño es considerado un hotspot de la conservación mundial de la biodiversidad. Hoy hay menos de 10 % de su área original. Por lo tanto, es necesario restaurar estos ecosistemas. Hay diversas maneras de alcanzar las principales metas de la restauración de los bosques, pero hay una falta de estudios ecológicos que analice la riqueza de especies de árboles como variable. Por lo tanto, el objetivo de este estudio fue investigar si hay una diferencia entre las restauraciones forestales en un gradiente de riqueza de especies de árboles que varía de 20, 60 a 120, usando la hojarasca como indicador. A cada mes, durante un año, esta fue recogida de las trampas de hojarasca previamente instaladas. Los resultados revelaron que la producción de hojarasca del bosque, en orden creciente de especies, fue de 5.370, 5.909 y 6.432 kg ha-1 año-1. Los análisis estadísticos no revelaron diferencia entre ellos. Consecuentemente, el bosque plantado de seis años de edad demostró que no hubo diferencia en la producción de hojarasca de la riqueza debido a la especies de árboles.

Summary 1.Climate models predict that the frequency, intensity and duration of drought events will increase in tropical regions. Although water withdrawal from deep soil layers is generally considered to be an efficient adaptation to drought, there is little information on the role played by deep roots in tropical forests. Tropical Eucalyptus plantations managed in short rotation cycles are simple forest ecosystems that may provide an insight into the water use by trees in tropical forests. 2.The contribution made by water withdrawn from deep soil layers to the water required for evapotranspiration was quantified daily from planting to harvesting age for a E. grandis stand using a soil water transfer model coupled with an ecophysiological forest model (MAESPA). The model was parameterized using an extensive dataset and validated using time series of the soil water content down to a depth of 10 m and water table level, as well as evapotranspiration measured using eddy-covariance. 3.Fast root growth after planting provided access to large quantities of water stored in deep soil layers over the first two years. Eucalyptus roots reached the water table at a depth of 12 m after 2 years. Although the mean water withdrawal from depths of over 10 m amounted to only 5% of canopy transpiration from planting to a harvesting age of 5 years, the proportion of water taken up near the water table was much higher during dry periods. The water table rose from 18 m to 12 m below ground over 2 years after the harvest of the previous stand, and then fell until harvesting age as evapotranspiration rates exceeded the annual rainfall. 4.Deep rooting is an efficient strategy to increase the amount of water available for the trees, allowing the uptake of transient gravitational water and possibly giving access to a deep water table. Deep soil layers have an important buffer role for large amounts of water stored during the wet season that is taken up by trees during dry periods. Our study confirms that deep rooting could be a major mechanism explaining high transpiration rates throughout the year in many tropical forests. This article is protected by copyright. All rights reserved.

Wood growth in trees depends on the acquisition of resources, and can vary with tree size leading to a variety of stand dynamics. Typically, larger trees obtain more resources and grow faster than smaller trees, but while light has been addressed more often, few case studies have investigated the contributions of water use and water use efficiency (WUE) within stands to isolate the tree-size dominance effect. Our sites were located near the cities of Aracruz and Eunapolis in Northeastern Brazil. We measured tree biomass growth, water use and WUE to explore patterns of growth among dominant and non-dominant trees in rainfed (1350 mm yr−1) and irrigated experimental stands in two high productivity tropical clones of Eucalyptus grandis × urophylla growing in clayey Ultisol soils. During the study period, irrigation supplied an additional 607 mm and 171 mm at the Aracruz and Eunapolis sites respectively. We tested two hypotheses; (1) larger trees transpire more water, and produce more wood per water used (higher water use efficiency, WUE) than smaller trees of the same clone and; (2) this pattern also applies if a water surplus is added via irrigation to alleviate water stress. Across both sites, we measured stand water use using sap flow sensors from August to December, and quantified wood growth on a tree-basis and then derived WUE, in kg wood per m3 of water transpired. Dominant trees showed higher rates of tree growth, water use and WUE than dominated trees for the two sites-clones and under both water supply regimes. Using the rainfed trees at Aracruz as an example, 50-kg trees grew 1.0 kg month−1 compared with growth of 100-kg trees of 3.8 kg month−1. The smaller trees would use water in a rate of 2.1 m3 month−1, compared with 3.1 m3 month−1 for the larger trees, demonstrating a higher WUE for the larger tree (1.2 kg m−3 versus 0.5 kg m−3). Our results suggest that manipulating stand density on heterogeneous stands, e.g. thinning, has the potential to minimize the tradeoffs between wood growth and tree water use in Eucalyptus grandis × urophylla plantations, mainly in tropical regions with seasonal water deficit. However, more research is needed to discern the underlying mechanisms responsible for higher WUE exhibited by dominant trees and distinct clones.

Increased soil carbon sequestration can potentially mitigate CO2 emission and can indicate sustainable forest management. This study aims to determine the relative influence of commercial plantation tree species on soil carbon following establishment on former tropical pastures. Soil carbon (organic horizon plus mineral soil from 0 to 45 cm) and stemwood productivity were quantified from 6 to 34 year-old conifer and broadleaf plantations in a sandy Oxisol (Typic Hapludox) in southeastern Brazil. Study plots consisted of ten pastures paired with broadleaf plantations and ten additional broadleaf plantations paired with conifer plantations. Pastures primarily consisted of Brachiaria decumbens Stapf., while broadleaf plantations were primarily Eucalyptus, but also included one plot each of three other broadleaf species. Conifer stands were made up of Pinus species. Average stemwood productivity (± standard error) was 9.7 (±1.0) Mg C ha−1 yr−1 for broadleaf and 5.7 (±0.5) Mg C ha−1 yr−1 for conifer plantations, but did not correlate to soil C. The soil C in the paired Pasture–Broadleaf plots averaged 36.0 ± 1.7 Mg C ha−1 in pastures and 36.8 ± 1.9 Mg C ha−1 in broadleaf plantations. The Broadleaf–Conifer plots averaged 38.3 ± 1.9 Mg C ha−1 for broadleaf plantations and 36.0 ± 1.6 Mg C ha−1 for conifers. Our results show little difference in soil C across vegetation types, providing evidence that conifer and broadleaf plantations overall maintain similar levels of soil carbon to pasture land-use up to 34 years following land conversion. Soil C differences between Pasture–Broadleaf pairs indicated a small decline in soil C accretion early after plantation establishment, followed by recovery to slightly higher accretion rates.

Leaf wetness duration (LWD) is recognized as a very important conditioner of crops and forests diseases, but clearly, there is a considerable gap in literature on temporal models for prediction of LWD in broad regions from standard meteorological data. The objective of this study was to develop monthly LWD models based on the relationship between hours of relative humidity (RH) ≥ 90 % and average RH for Brazil and based on these models to characterize the temporal and spatial LWD variability across the country. Two different relative humidity databases, being one in an hourly basis (RHh) and another in a monthly basis (RHm), were used. To elaborate the LWD models, 58 automatic weather stations distributed across the country were selected. Monthly LWD maps for the entire country were prepared, and for that, the RHm from the 358 conventional weather stations were interpolated using geostatistical techniques. RHm and LWD showed sigmoidal relationship with determination coefficient above 0.84 and were highly significant (p